Applying probabilistic flood forecasting in flood management
Research showing how probabilistic forecasts could be used to aid decision making in future flood incident management.
Documents
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Details
Objectives
This project delivered a set of reports to illustrate how probabilistic flood forecasting could be used to decide whether to take action when a flood is forecast. Probabilistic forecasting provides uncertain information in the forecasting of floods. The information is mainly aimed at professionals and decision makers responsible for forecasting and responding to the risk of flooding.
The reports provide evidence, suggested approaches and case studies to demonstrate how probabilistic forecasts could be used to aid decision-making in flood incident management.
Flood forecasts are uncertain. Unlike deterministic forecasts, probabilistic flood forecasts try to calculate and represent this uncertainty to enable longer forecasting and warning lead times. They support risk and impact based decision-making. They also help us to better understand the range of possible outcomes, so that the potential impacts can be communicated to communities.
Outcome
The additional information provided by probabilistic forecasts raises important questions, such as:
- what action should be taken when some forecasts predict flooding while others do not?
- how can we best use probabilistic information to inform operational decisions which often require clear choices, such as whether to operate certain structures or not?
Decision-making during flood events is influenced by many factors ranging from ‘hard’ evidence (forecasts, observations and data) to important ‘softer’ factors (local knowledge, recent flood history and forecast performance, current risk appetite). Decision making during incidents is a dynamic process which should vary depending on the specific situation.
This research develops a flexible and simple framework to use probabilistic forecasts to support decision-making, taking softer factors into account. It develops three proof of concept methods and tests them on case studies. The report and illustrative guide explain how these methods could be applied to a variety of forecasting situations of different complexities and at varying times ahead of a potential flood.
The research makes an important contribution to our evidence base and provides a valuable resource to practitioners and researchers. It’ll help inform the future direction of probabilistic flood forecasting as part of wider developments in flood incident management.
Going forward
Decision-making with probabilistic information is an active research and development area and we expect new approaches to become available over time. The proof of concept approaches described here are illustrations of how probabilistic flood forecasts could be used to support decision-making. They’re not intended to be fixed and definitive operational procedures to be followed.
This project ran from 2009 to 2013.